This relates to networks that use both WiMAX and WiFi communication through central points.
In some networks, the base station may communicate via Worldwide Interoperability for Microwave Access (WiMAX) (IEEE Std. 802.16-2004, IEEE Standard for Local and Metropolitan Area Networks, Part 16: Air Interface for Fixed Broadband Wireless Access Systems IEEE New York, N.Y. 10016) with a central point which, in turn, communicates with a personal area network via WiFi (IEEE Std. 802.11 (1999 Jul. 15) Wireless LAN Medium Access Control (MAC) and Physical Layer Specifications). The central point may then be said be a co-located WiFi and WiMAX transceiver.
WiFi and WiMAX combination radios provide wireless, wide area network (WWAN) access via WiMAX and wireless personal area network (WPAN) service via WiFi at the same time. A WiMAX base station provides WiMAX access to multiple personal area network cells. Within each such cell, a multi-radio platform with co-located WiFi and WiMAX radio serves as the central point that can communicate externally of the personal area network using WiMAX, while also acting as the access point for personal area network clients.
Due to strong co-located radio interference and resource constraints, co-located WiMAX and WiFi radios cannot operate at the same time. The WiFi radio usually has to yield to the WiMAX radio. The coordination of operations between WiFi and WiMAX can be performed, for example, through a MAC coordinator, where the resource is arbitrated between co-located radios and co-located radios effectively operate in a time division multiplexed fashion.
In general, scheduled WiMAX activities are given a higher priority than WiFi activities, so that WiFi can only operate when WiMAX is not in conflicting operations. At the same time, personal area network central points compete with each other for common channel access over WiFi. As a result, the different ways of scheduling WiMAX activities among the central points leads to different levels of WiFi channel contention among the central points. Consequently, scheduling of WiMAX network traffic affects the overall throughput of the coexisting personal area networks. Generally, existing WiMAX scheduling algorithms allocate solely based on WiMAX performance criteria. Without considering coexisting conditions, these schedules may produce WiMAX scheduling patterns that lead to devastating personal area network throughput.